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Hole concentration vs. Mn fraction in a diluted (Ga,Mn)As ferromagnetic semiconductor

Published online by Cambridge University Press:  21 March 2011

Raimundo R. dos Santos
Affiliation:
Inst. de Física, Univ. Fed. do Rio de Janeiro, CP 68.528, Rio de Janeiro–RJ, 21945-970, Brazil
L. E. Oliveira
Affiliation:
Instituto de Física, Unicamp, CP 6165, Campinas-SP, 13083-970, Brazil
J. d'Albuquerque e Castro
Affiliation:
Inst. de Física, Univ. Fed. do Rio de Janeiro, CP 68.528, Rio de Janeiro–RJ, 21945-970, Brazil
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Abstract

The dependence of the hole density on that of Mn sites in Ga1−xMnxAs is studied within a mean-field approach to the hole-mediated ferromagnetism in III-V Mn-based semiconductor compounds. We parametrize the hole concentration, p, as a function of the fraction of Mn sites, x, in terms of the product m* (Jpd)2 (where m* is the hole effective mass and Jpd is the Kondo-like hole/local-moment coupling), and the critical temperature Tc. By fitting m* (Jpd)2 to experimental data for Tc(x), we establish the dependence of p on x, which is interpreted in terms of a reentrant metal-insulator transition taking place in the hole gas.

Type
Research Article
Copyright
Copyright © Materials Research Society 2002

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